Namespace for various particle management tools. More...

Typedefs
template<class P >
using	ParticleMerger = std::function< void(List< P > &a_particles, const CellInfo &a_cellInfo, const int a_numTargetParticles)>
	Concept for splitting/merging particles.

template<class P >
using	BinaryParticleReconcile = std::function< void(P &p1, P &p2, const P &p0)>
	Declaration of a reconciliation function when splitting particles.

Functions
template<class P , Real &(P::)() weight, const RealVect &(P::)() const position>
std::vector< std::shared_ptr< KDNode< P > > >	recursivePartitionAndSplitEqualWeightKD (typename KDNode< P >::ParticleList &a_inputParticles, const int a_maxLeaves, const BinaryParticleReconcile< P > a_particleReconcile) noexcept
	Recursively build a KD-tree following the "equal weight" principle when partitioning nodes.

template<typename P , typename T , typename >
void	removePhysicalParticles (List< P > &a_particles, const T a_numPhysPartToRemove) noexcept
	Remove physical particles from the input particles.

template<typename P >
void	deleteParticles (List< P > &a_particles, const Real a_weightThresh) noexcept
	Remove particles if their weight is below the input weight.

template<typename T , typename >
std::vector< T >	partitionParticleWeights (const T a_numPhysicalParticles, const T a_maxCompParticles) noexcept
	Partition particle weights among a number of computational particles.

template<typename T , typename >
T	partitionParticles (const T a_numParticles)
	Partition particles so that all MPI rank draw a cumulative number of particles equal to a_numParticles.

template<typename P , typename T , typename >
void	drawRandomParticles (List< P > &a_particles, const T a_numParticles, const std::function< RealVect()> &a_distribution)
	Draw a specified number of random particles distributed according to a predefined distribution.

template<typename P , typename T , typename >
void	drawSphereParticles (List< P > &a_particles, const T a_numParticles, const RealVect a_center, const Real a_radius) noexcept
	Draw particles in a sphere.

template<typename P , typename T , typename >
void	drawBoxParticles (List< P > &a_particles, const T a_numParticles, const RealVect a_loCorner, const RealVect a_hiCorner) noexcept
	Draw particles in a box.

template<typename P , typename T , typename >
void	drawGaussianParticles (List< P > &a_particles, const T a_numParticles, const RealVect a_center, const Real a_radius) noexcept
	Draw particles from a Gaussian distribution.

Detailed Description

Namespace for various particle management tools.

Typedef Documentation

◆ BinaryParticleReconcile

template<class P >

using ParticleManagement::BinaryParticleReconcile = typedef std::function<void(P& p1, P& p2, const P& p0)>

Declaration of a reconciliation function when splitting particles.

This is, for example, passed into the KD-tree equal-weight partioning structure, which may split a particle such that the weight of the two nodes differ by at most one physical particle. By default, that method will call the particle copy constructor, but this function permits the user to input a reconciliation function that manipulates other class members in the split particles.

◆ ParticleMerger

template<class P >

using ParticleManagement::ParticleMerger = typedef std::function< void(List<P>& a_particles, const CellInfo& a_cellInfo, const int a_numTargetParticles)>

Concept for splitting/merging particles.

Parameters

[in,out]	a_particles	Particles to be merged/split
[in]	a_cellInfo	Cell info
[in]	a_numTargetParticles	Number of target particles

Function Documentation

◆ deleteParticles()

template<typename P >

void ParticleManagement::deleteParticles	(	List< P > &	a_particles,
		const Real	a_weightThresh
	)

inlinenoexcept

Remove particles if their weight is below the input weight.

Parameters

[in,out]	a_particles	Input list of particles. Must have a weight function.
[in]	a_weightThresh	Weight threshold for removal

◆ drawBoxParticles()

template<typename P , typename T , typename >

void ParticleManagement::drawBoxParticles	(	List< P > &	a_particles,
		const T	a_numParticles,
		const RealVect	a_loCorner,
		const RealVect	a_hiCorner
	)

inlinenoexcept

Draw particles in a box.

The implementation will partition a_numParticles among the ranks so the total number of particles drawn is a_numParticles. P is the particle type (must have a RealVect& position() function) and T is an integer type.

Parameters

[out]	a_particles	Output particles (different for each rank)
[in]	a_numParticles	Number of particles
[in]	a_loCorner	Low corner of box
[in]	a_hiCorner	High corner of box

◆ drawGaussianParticles()

template<typename P , typename T , typename >

void ParticleManagement::drawGaussianParticles	(	List< P > &	a_particles,
		const T	a_numParticles,
		const RealVect	a_center,
		const Real	a_radius
	)

inlinenoexcept

Draw particles from a Gaussian distribution.

The implementation will partition a_numParticles among the ranks so the total number of particles drawn is a_numParticles. P is the particle type (must have a RealVect& position() function) and T is an integer type.

Parameters

[out]	a_particles	Output particles (different for each rank)
[in]	a_numParticles	Number of particles
[in]	a_center	Gaussian blob Center
[in]	a_radius	Gaussian blob radius

◆ drawRandomParticles()

template<typename P , typename T , typename >

void ParticleManagement::drawRandomParticles	(	List< P > &	a_particles,
		const T	a_numParticles,
		const std::function< RealVect()> &	a_distribution
	)

inline

Draw a specified number of random particles distributed according to a predefined distribution.

The implementation will partition a_numParticles among the ranks so the total number of particles drawn is a_numParticles. P is the particle type (must derived from BinItem) and T is an integer type.

Parameters

[out]	a_particles	Output particles (different for each rank)
[in]	a_numParticles	Number of particles
[in]	a_distribution	Particle distribution. Must return a random position when calling the function.

◆ drawSphereParticles()

template<typename P , typename T , typename >

void ParticleManagement::drawSphereParticles	(	List< P > &	a_particles,
		const T	a_numParticles,
		const RealVect	a_center,
		const Real	a_radius
	)

inlinenoexcept

Draw particles in a sphere.

The implementation will partition a_numParticles among the ranks so the total number of particles drawn is a_numParticles. P is the particle type (must have a RealVect& position() function) and T is an integer type.

Parameters

[out]	a_particles	Output particles (different for each rank)
[in]	a_numParticles	Number of particles
[in]	a_center	Sphere center
[in]	a_radius	Sphere radius

◆ partitionParticles()

template<typename T , typename >

T ParticleManagement::partitionParticles ( const T a_numParticles )

inline

Partition particles so that all MPI rank draw a cumulative number of particles equal to a_numParticles.

Parameters

[in] a_numParticles Total number of particles to be drawn.

Returns: Returns the number of particles drawn by each rank.

◆ partitionParticleWeights()

template<typename T , typename >

std::vector< T > ParticleManagement::partitionParticleWeights	(	const T	a_numPhysicalParticles,
		const T	a_maxCompParticles
	)

inlinenoexcept

Partition particle weights among a number of computational particles.

Parameters

[in]	a_numPhysicalParticles	Number of physical particles.
[in]	a_maxCompParticles	Maximum number of computational particles

◆ recursivePartitionAndSplitEqualWeightKD()

template<class P , Real &(P::*)() weight, const RealVect &(P::*)() const position>

std::vector< std::shared_ptr< KDNode< P > > > ParticleManagement::recursivePartitionAndSplitEqualWeightKD	(	typename KDNode< P >::ParticleList &	a_inputParticles,
		const int	a_maxLeaves,
		const BinaryParticleReconcile< P >	a_particleReconcile = `[](P &p1, P &p2, const P &p0) -> void { }`
	)

inlinenoexcept

Recursively build a KD-tree following the "equal weight" principle when partitioning nodes.

Parameters

[in,out]	a_inputParticles	Input particles. These are destroyed on output.
[in]	a_maxLeaves	Maximum number of leaves in the tree.

Returns: Returns leaf nodes containing the particles

If the number of leaves is a factor of two, leaves exist on the same level and the weight in each node will differ by at most one physical particle. The template parameters are

P -> Particle type P::*weight -> Function pointer to particle weight P::*position -> Function pointer to particle position.

A possible call signature is e.g. recursivePartitionAndSplitEqualWeightKD<P, &P::weight, &P::position>.

The user can input a particle reconciliation function that manipulates the particle properties of the split particles. By default, the split particles will use the copy constructor and thus inherit class members from p0, with the exception of the particle weights. The reconcile function lets the user manipulate other particle properties, e.g. ones that are not properly captured by the particle copy constructor, or that need some other form of reconciliation.

◆ removePhysicalParticles()

template<typename P , typename T , typename >

void ParticleManagement::removePhysicalParticles	(	List< P > &	a_particles,
		const T	a_numPhysPartToRemove
	)

inlinenoexcept

Remove physical particles from the input particles.

Parameters

[in,out]	a_particles	Input list of particles. Must have a weight function.
[in]	a_numPhysPartToRemove	Number of physical particles to remove

Note: May fail if particle weights are not (close to) integers.

Typedefs

Functions

Detailed Description

Typedef Documentation

◆ BinaryParticleReconcile

◆ ParticleMerger

Function Documentation

◆ deleteParticles()

◆ drawBoxParticles()

◆ drawGaussianParticles()

◆ drawRandomParticles()

◆ drawSphereParticles()

◆ partitionParticles()

◆ partitionParticleWeights()

◆ recursivePartitionAndSplitEqualWeightKD()

◆ removePhysicalParticles()